Ficoll, dextran, and glucose applied from the cytoplasmic side of MscS changed the inactivation time constant, τ, of the channels in a manner inversely proportional to their molecular weight. Change of τ is presented as a function of a fractional osmolarity of each cosolvent. Black, shaded, and open symbols represent effects of ficoll, dextran, and glucose, respectively, and each symbol type (squares, triangles, or circles) represents one experiment.